Cartridge



, 18 Feb. 28, 1933. J, HOLTHE 1,899 6 CARTRIDGE Filed July T, 1932 Patented Feb. 28, i933 JOHN HOLTHE, F STRATFORD, CONNECTICUT CARTRIDGE Application led `Tuly 7, 1932. Serial No. 621,188.

This invention relates to cartridges, especially of the type used with small arms.

Heretofore, it has been customary to make the cartridge of two parts, one being a hollow drawn metal casing and the other being a' projectile closing the front end of the shell or 1casing, the charge being located in the she l.

This form of cartridge is not only expen- 0 sive to manufacture due to the man drawing and annealing operations require to produce the shell, but-it also requires that provision be made and time be taken for ejecting the casing or shell after the shot has been 5 red. l

It is one of the important objects of the present invention to provide ammunition in which the projectile is so formed 'as to constitute Yboth the projectile and the casing or housing for the charge, and to provide means for closing the rear end of the projectile, which means is destroyed as a result of the firing of the arm. For this purpose, the projectile is made to have a substantial cavity for the charge, and a plug of celluloid or the like is provided to close its rear end.

Another important object of the present invention is to provide for decreasing the air resistance of the projectile and thus give it increased range and effectiveness. This is accomplished by the present invention by providing the projectile with an axial bore eX- tending therethrough, so that air through which the projectile passes may be divideda part going through the bore and the other part going around the exterior of the projectile in the form of slip-streams. In this way, formation of densified areas ahead of the bullet is avoided. Preferably, the axial bore of flares forwardly sharply from a point near its front end and from the same point flares gradually toward the rear end of the projectile at which the diameter of the bore is substantially the same as the outside of the projectile. In this way, the formation of pockets or vacuities behind the projectile which would tend to retard it in its flight is eliminated.

Such a hollow projectile could not, however, be discharged from a tire arm, and itis necessary to plug the bore for at least the initial part of its flight.

It has been suggested heretofore to use more or less hollow projectiles, and in such cases it was proposed to close the axial bore or opening by a metal plug which was supposed to be ejected from the projectile at some point in its flight by the pressure of the air streams thereon. The work of ejecting this plug would, of course, retard the flight of the bdl- Accordingly, an important feature of this invention is the provision of a plug for the hollow projectile which, of itself, becomes destroyed and is eliminated from the bore. This is accomplished in the preferred form of this invention .by closing the forward end of the bore by means of a slow-burning material which is ignited by the main charge. If slow-burning gun powder or the like is employed for this purpose, the gases resulting from its combustion will expand in the rear end of the hollow projectile and be emitted from the open rear end thereof. These gases will, therefore, tend to fill any pockets which may tend to form at the rear of the projectile prior to the opening of the cavity. The slow-burning plug is prevented from being blown out through the front end of the projectile .by being firmly compressed therein and because of the tapering bore in which it is compressed. The material of the slow- .burning plug may be such as to generate gases or flames at such a rate that the emission of the latter-from the rear end of the projectile serves to accelerate the latter, and thus increase its range or eii'ectiveness.

In such fire-arms as machine guns, the rapidity with which the successive shots may be fired depends to some extent upon the time required to insert and eject the bullet. With the projectile and shell of the present invention, the ejecting operation is eliminated entirely. Accordingly, the rapidity with which the shots may be fired is materially increased.

In some cases, it is unimportant whether or not there is anything left to be ejected after the discharge, and in these cases the quired in its fabrication.

ythe projectile after the air been burned out.

rear end of the projectile may be formed of metal.

As a matter of fact, the hollow projectile,

of the present invention may be employed with a cartridge shell, particularly in eases where an extra heavy firing charge is required, or where a shorter projectile is desired. Even in such cases, an economy in the cost of producing the cartridge is eected, for some part of the charge may be carried in the hollow projectile, and the shell may accordingly be made shorter than would otherwise be requireds However, it is preferable to eliminate the use of the shell completely, for this is a costly part to make due to the fact that successive drawing and annealing operations are re- Fig. 5 is a plan view of the present invention applied to the standard cartridge shell.

Fig. 6 is a section of that form of the present invention shown in Fig. 5, and taken on line 6 6 in the latter figures.

Fig. 7 is a sectional view similar to Fig. 2, of a further modied form of the present invention.

With that form of the present invention shown in Figs. 1 to 4, there is provided'a projectile 10 made of lead, copper, or any other suitable material, preferably slightly pointed as at 11 to more readily cut through the air. Now, it should be particularly noted that this projectile is provided with an axial bore 12 therethrough, preferably conical in shape with its smallest diameter13 near the front thereof and gradually tapering to a larger diameter near the rear thereof. This bore 12 atits front end is sealed with a plug 14 of slow burning powder; for example, a mixture of regular powder together with charcoal and clay which, upon drying, forms quite a solid plug and one which is adapted to remain in place and withstand a considerable pushing impact. v

The part of the bore 12 between the rear end of the plug 14 and the rear end of the projectkile 10 forms a chamber 15 for the reception of a properly proportioned main propelling explosive charge of gun powder, theY grains of which are indicated at 16. This chamber 15 is sealed with a. plug 17 of suitable material. Preferably, this plug or disk 17 is provided with a neck portion 18 adapted to be forced into a stepped portion 19 of the bore 12 to hold the disk in place and prevent the powder from release and loss. A flange 20 on the disk locates the disk in the stepped bore and limits its movement therein. A regular percussion or firing cap could be placed in this disk for engagement by a firing pin in the fire arm with which the cartridge is used. However, according to the present invention, the disk is provided with a small bore 21 and a deposit of fulminate 22 or other highly explosive material is deposited in the small bore and a cupr23 of vsuitable inflammable material is forced into the bore to form a. weather and shock protective covering for the fulminate.

Use of this form. in the present invention is as follows. The cartridge 10a; formed by the present invention is placed in firing position in the fire-arm with which it is intended to be used. Now, when the user pulls the trigger, the firing pin impinges against the fulminate 22 to ignite the latter, and this in turn'ignites the main supply of powder 16 to form highly compressed gases, which as they expand, eject the projectile 10 forwardly through the bore of the gun. These gases, because of the ta ering bore12 and because of the stop forme by the back of the plug 14, are concentrated near the axial center of the projectile and exert their maximum pushing force near the front of the projectile, preferably at about the center of gravity. This is a particularly important advantage with the projectile of the present invention for, by having the maximum pushing force near the axial center of the projectile, more accurate Hight is assured-an advantage which is further enhanced by having the center of gravity of the projectile near the front thereof and especially by having the maximum pushing force of the explosive charge extend to a point near the center of gravity of the bullet.

When the main charge 16, which is preferably a highly explosive and quick burning powder, is fired, it ignites the plug 14 within the projectile 10 so that it burns and is consumed during Hight of the projectile through the bore of the gun and durmg the initial part of its flight through free air. Preferably, the material of which this plug is made is so proportioned that it is certain to withstand the pushing impact of the main explosive charge. The tapered bore 12 facilitates this action, for, should the plug be forced forwardly in the bore 12 when the main charge 16 is exploded, the tapered' bore serves to more tightly wedge the plug and prevent it from being forced out of the projectile. The plug 14 may be so made and proportioned as to burn out immediately after the projectile 10 has passed out of the gun, or it may be made to burn for a suiliciently long time to permit the general course of the projectile to be ob served. When the plug has burned out, there is formed a passage 12a through the center of the bullet for air which would normally retard it in its Hight. This air passage prevents the building up of air pressure ahead of the projectile and avoids the formation of eddy currents and vacuums at its back end. The composition forming this plug is preferably such that it forms additional hlghly expansible gases to Hll the bore in the gun and accelerate the bullet on its Hight therethrough, and to increase the original impetus given by the main Hring charge. Besides, after the projectile has left the gun, the gases formed by the burning of the material of the plug tend to till any vacuum which might tend to form behind the projectile while the passage 12a is closed, and may be made to act in the nature of a rocket to give further propelling power to the projectile.

The plug or disk 17, according to the present invention, may be made of a highly combustible material such as Celluloid and the like, and is arranged to remain substantially whole during the firing of the main charge 16 and to quickly consume itself by Hre immediately thereafter.

As has been indicated, the projectile 10 may form the main body of the cartridge of this invention, and it in turn is projected from the bore in the gun in the form of a bullet. With the self-consuming disk 17, there is n0 scrap shell or any other mechanical residue after the cartrid e has been fired. After firing a cartri ge of the present invention, it is merely necessary to automatically or manually drop another cartridge of the same form in the cartridge chamber of the gun and tire it. With it there is nothing to eject from the gun, and in automatic lire-arms the shots per minute may be materially increased by its use. Moreover, the cost of providing shells is eliminated. Yet, the projectile may contain suHicient mass to do the work for which it is intended, and it may carry a suHiciently large powder charge for its purpose.

It should be particularly noted that the airpassage 12a gradually expands from near the front toward the rear end of the projectile 10,

so that the air rushing therethrough may expand and be passed almost to the outer periphery of the projectile, thereby reducing to a minimum any possibility of the formation of a vacuum or eddy currents at the rear of the bullet, which would tend to retard it in its Hight. This relatively large diameter of the bore at this point and consequently thin shell for the base of the projectile is made possible according to the present invention by having it so constructed that the main force of the explosive charge 16 is transmitted toward the axial centre of the bullet and near the front end thereof where the walls are relatively thick.

Preferably the bore 12 is provided with a section 24 at the front end of the projectile which Hares'sharply and serves to direct a larger volume of the nose resistant air through the projectile and provide a larger volume to fill the vacuum at the back end of the projectile while it is in Hight.

A further advantage of reducing the vacuum at the rear of the bullet to a minimum is reduction in the turbulence of the projectile while in Hight and a consequent reduction in the possibility of tumbling.

In Figs. 5 and 6 there is shown a modifie form of the present invention wherein the projectile of the present invention is shown as applied to a cartridge shell 25. The projectile 10 and plug 14 shown with the preferred form of the present invention may be used in this form of the invention; or they may be used with substantial modification if desired. However, when a shell is employed as in Figs. 5 and 6 the main charge 16a of powder is placed within both the shell 25 and the projectile 10, the latter beingvforced into a neck 26 of the shell, and keeping the powder in place. This form of cartridge is especially suited for long range shooting, because a large supply or main powder charge 16a may be stored therein and in the projectile bore 12 without increasing the length of the .cartridge.

This cartridge is placed into the iiring chamber portion of the gun with which it is intended to be used and when the gun is manipulated the tiring pin engages a usual or suitable iiring cap 27 in the shell to ignite the main charge 16a, and the gases formed thereby push against the back end of the plug 14 to push the projectile free from the neck 26 and speed it through the 'bore of the gun. The plug 14 is ignited by the main charge 16a and burns out during the initial part of the Hight of the projectile to provide a .free passage for the air in the same manner as in the form of the invention illustrated in Figs. l to 4.

' In Fig. 7 there is shown a modification of the form of cartridge shown in Figs. 1 to 4 inclusive. It may in all respects be like the latter except for a diii'erent form of rear plug or base 17a which is made of metal or some other material which is not inHammable. This disk 17a is provided with a neck portion 27 adapted to be forced into the stepped bore 19 of the projectile 10 to seal the main powder charge 16 between it and the 14 of slow burning powder. The diskis also provided with a Hange 28 to limit movement of the disk into the projectile and to locate the cartridge in the firing chamber. A usual or suitable firing cap 29 is located in the disk for thepurpose of igniting the main charge 16.

The present invention has been described as embodied in a cartridge for use in small fire arms, however, it will be vreadily appreciated that it may also be embodied in larger guns to advantage.

Other variations and modifications may be made within the scope of this invention and portions may be used without others.

Having thus described the inventionvhat I claim as new and for which I desire to obtain Letters Patent, is:

1. A cartridge comprising a projectile having a bore extending axially therethrough; a plug of slovv burning material closing the 'front end of the bore; an explosive charge Within said bore; a. metal plug in the rear end of the bore forming a seal for the explosive charge. v

2. A cartridge comprising a projectile having a bore extending axially therethrough; a plug of slow burning material near the front end of the bore; an explosive charge within said bore; and a celluloid plug forming a seal 'for the explosive charge.; adapted to be destroyed by the explosive charge Within the bore of the gun With Which the cartridge is used and to make unnecessary the removal of any cartridge scrap before placing another cartridge in liring position. v V

3. A cartridge comprising a projectile having a bore extending axially therethrough; a plug of slovvy burning material near the :front end of said bore, and adapted to burn' out during the initial part of the Hight of the projectile; an explosive charge Within said bore; and a plug of slow burning material in the other end of said bore serving to seal the high explosive charge within the bore.

4. A projectile having a tapering bore extending axially therethrough; and a plug of slow burning material adapted to burn out during the initial part oi' the flight of the projectile, said plug being tapered substantially like the tapered bore so as to Wedge tighter therein when subjected to the pushing impact of an explosive Hight impelling charge.

5. A projectile having along bore extend-l ing axially therethrough and Haring from near the front toward the rear Where it has substantially the same diameter as the outside of the projectile; an explosive char e within said bore; and a plug of relative y slow burning material ignited by the main explosive charge and adapted to burn out during the initial art of the Hight of the bullet to open up t e bore and form an air passage through the rojectile.

6. A projectile having a long bore extending axially therethrough and Haring from near the front toward the rear where it has substantially the same diameter as the outside ot' the projectile; an explosive charge within said bore; and a plug of relatively slow burning material ignited by the main explosive charge and adapted to burn out during the initial part of the Hight of the bullet to open up the bore and form an air passage through the projectile, said plug being made of gas forming material which While burning ejects from the rear open end of the projectile a gas which prevents the,

formation of a Hight retarding vacuity in back of the projectile.

7. A projectile having a long bore extending axially therethrough and Haring from near the front toward the rear `Where it has substantially the same diameter as the outside of the projectile; an explosive charge within said bore; and a plug of relatively slow burning material ignited by the main explosive charge and adapted to burn out during the initial part of the Hight of the bullet to open up the bore and form an air passage through the projectile, said plug being made of gas forming material which While burning ejects from the rear open end ofthe projectile a gas which prevents the formation of a Hight retarding vacuity in back of the projectile, the expulsion of said'gas from the rear end of the projectile serving to drive the projectile forwardly. 'i

8. A projectile having a bore extending axially therethrough, said bore Haring t0- vvard lthe rear to substantially the same diameter as lthe outside of the projectile and serving to diH'use the air, which passes through the bore, at the back of the bullet t0 a point Which prevents the regular 'air currents which sweep over the bullet from forming a Hight restraining air pocket in back of the projectile during its Hight, and a self-destroying plug closing the bore adjacent the front end thereof during the initial part of the Hight of the projectile.

Signed at Bridgeport, in the county of Fairfield, and State of Connecticut, this 5th day of July, 1932. JOHN HOLTHE. 

